FIG. 1.

PIAS proteins interact with SUMO-1 and Ubc9 in vitro. ARIP3, ARIP3Δ347-418, ARIP3Δ467-487, Miz1, PIAS1, and PIAS3 were labeled with [³⁵S]methionine by translation in vitro and incubated with glutathione-Sepharose-bound GST, GST-SUMO-1, or GST-Ubc9. After extensive washings, bound proteins were eluted with SDS sample buffer, resolved by SDS-10% PAGE, and visualized by fluorography. Lanes i, input samples representing 10% of the amount of labeled proteins incubated with the matrices.